President Obama thanked U.S. armed forces, veterans and their families at the first inaugural ball Monday evening, and then he danced with his wife, first lady Michelle Obama, to Jennifer Hudson's rendition of Al Green's "Let's Stay Together," before heading to a second ball at the Walter E. Washington Convention Center, Politico reported.

The president began his round of inaugural ball events at the Commander-in-Chief's ball, and then moved down the hall to his second, and final ball of the evening, the public Inaugural Ball. Both balls were held at the Washington Convention Center, according to The Huffington Post.

About 40,000 guests were reported to attend both events.

Obama said he wanted to "express extraordinary gratitude not just of me as your commander in chief but the thanks of all the American people." He specifically thanked the senior enlisted offers from all branches of the military, Gen. Martin Dempsey and his deputy Adm. James Winnefeld, Jr., plus wounded warriors, junior enlisted officers, "amazing military families including the families of the fallen," members of the Tuskegee Airmen and recipients of the Medal of Honor, according to CBS News live coverage.

Glancing around the room full of U.S. armed service members, almost all dressed in full uniform, he spoke of "delivering justice" to Osama Bin Laden and giving Afghans a chance "to determine their own destiny." The president then spoke to some members on the ground in Afghanistan by videolink, thanking them for their service and reminding them, "when you get back home, you're gonna be greeted by a grateful nation."

From Politico:

"This party is just another way to say something we can never say enough: thank you for volunteering, thank you for stepping up, thank you for keeping us strong, thank you for always making us proud. I have no greater honor than being your commander-in-chief," he said. "It is because of you that we were able to end the war in Iraq. Because of you, we delivered justice to Osama bin Laden. Because of you, it is possible to give Afghans a chance to determine their own destiny. We are going forward and we will keep the fighting force that the world has ever known."

After his speech, the President invited first lady Michelle Obama, clad in an ankle-length ruby-colored chiffon dress by Jason Wu, to the stage and thanked her for inspiring him, and for making him "a better man, and a better president." The couple danced to Al Green's "Let's Stay Together," performed by Jennifer Hudson, before exchanging dances with members of the military.

The couple then headed to their last inaugural event, where they again danced to Jennifer Hudson's cover of "Let's Stay Together."

An impressive list of other celebrities made appearances throughout the evening, including Usher, John Legend, Katy Perry, Marc Anthony and Stevie Wonder.

The Washington Post reported that President Obama "trimmed the fat off the inauguration festivities" by cutting down the number of balls he attended from 10 to two, giving the couple a chance to relax and celebrate.